Present status and "future risk" of rising dementia cases in India cause of concern

India constituting 18 % of the world's total population, is expected to compose 15.4 % of the world's total elderly people aged 60 years and older in the "future". The Indian ageing graph is likely to increase to nearly 20 % by 2050 due to escalating life expectancy among the Indian population.

One of the significant risk factors for dementia is "ageing". The prevalence of dementia has increased repeatedly in India. The current situation with data unavailability and non-accuracy remains challenging due to the lack of a nationally representative study.

Disconcerting results from previous studies have displayed heterogeneous results, compromising the true prevalence of dementia cases in India.

A team of researchers from the USA, in collaboration with Indian researchers from the National Institute of Mental Health and Neurosciences (USA), All India Institute of Medical Sciences (New Delhi) and other medical colleges from India, conducted the first national study of dementia in India.

The main objective was to determine the dementia burden at national and state levels using LASI and LASI-DAD, representative of the country's ageing studies. The study has importance in building health policies in India, both national and state-specific.

The conclusive study points are:

• In northern India, among eight states, Jammu & Kashmir have the highest prevalence of dementia, and Delhi has the lowest, with 11 % and 4.5 %, respectively.
• Dementia prevalence in other northern states for Himachal Pradesh, Punjab, Uttarakhand, Haryana, Rajasthan and Uttar Pradesh constituting 8%, 5 %, 6 %, 5.7 %, 7 % and 7.9 %, respectively.
• In Eastern India, the prevalence of dementia in Assam was 8 %.
• In Western states, the dementia prevalence in Gujrat and Maharashtra was 6 % and 7.6 %, respectively.
• In Southern India, the prevalence in Andhra Pradesh, Karnataka, Tamil nadu, Kerala and Telangana was 7.7 %, 7.6 %, 6 %,8 % and 8%, respectively.
• Central India, including Madhya Pradesh and Chhattisgarh, have a 6.7 % and 6.9 % prevalence, respectively.
• The estimated prevalence of dementia for adults aged 60 years and older is 7.4%.
• 88 lakh Indians aged 60 years and older have dementia.
• The age-standardized prevalence for men and women is 6.3% and 9.6 %.
• Sex predilection is for females, "double" in comparison to males.
• The prevalence is higher in rural areas than in urban.
• Concerning literacy, dementia prevalence is higher among uneducated people without formal education.

The researchers predicted that the cases of dementia will rise to 169 lakhs in 2036.

Education is a vital interplay in the context to risk factors of dementia accounting for under-nutrition, uncontrolled heart disease, and indoor air pollution. The rapid increase in cases of heart disease in India is bound to expand dementia in future. There lies a difference in the study results of the present study compared to previous studies.

Our dementia prevalence is similar to those of the US and UK at 8.6 % and 7.1 %, they said.

The study's prime limitation was 13% of the LASI sample participated in the LASI-DAD study, which does not provide details at the state level. The other limitations were substantial standard errors, availability of information, and interview bias.

The final words of conclusion by researchers are,

In 2010, the Alzheimer's and Related Disorders Society of India 2010 said that 3.7 million Indians had dementia which would double by 2030, but we say this to be an "underestimate."

The urgency lies in preventing dementia and scaling up policies since the burden of dementia is uneven in different states, so there is a requirement for a different level of planning and support.

The expected future research should be on early-onset dementia and subtypes of dementia. Approaches like telemedicine, algorithmic classification of dementia based on neuropsychological test performance and informant reports can be adopted. Moreover, there should be a better understanding of the relationship between education and dementia.

Further reading:

https://alz-journals.onlinelibrary.wiley.com/doi/full/10.1002/alz.12928